Tata Motors, India's biggest carmaker, said Managing Director Karl Slym died in a fall from the Shangri-La hotel in Bangkok.

Slym, 51, was staying at the hotel when the fall occurred, a spokeswoman at the Mumbai-based company said by telephone yesterday, without elaborating.

The Englishman, who joined Tata Motors in 2012 after a 17-year stint at General Motors, was the top executive for the carmaker's operations excluding the Jaguar Land Rover luxury unit.

Slym came to Tata Motors from GM's Chinese unit and was working to steer the carmaker through the biggest slowdown in more than a decade in Asia's third-biggest economy.

He sought to reposition the failing Nano as a ''second car'' after buyers shunned the $US2300 compact pitched as an inexpensive alternative to motor scooters.

''Karl was beginning to make long-term changes at Tata Motors,'' Vikas Sehgal, managing director for the automotive sector at Rothschild & Sons in London, said in a telephone interview.

''His loss will be felt deeply by Tata Motors.''

Bangkok police had no immediate comment when contacted by Bloomberg News last night and said they may release information later today.

Slym had gone to the city to attend a board meeting of Tata Motors Thailand, the carmaker said in an emailed statement.

The Society of Indian Automobile Manufacturers, which has forecast the first annual drop in passenger-vehicle sales in more than a decade, said this month the industry was still going through a rough patch as an economic slowdown damps demand for cars and SUVs.

The nation's passenger-vehicle sales slid 5.7 per cent in the nine months ended December 31, the organisation for the country's carmakers reported January 9.

''Karl was providing strong leadership at a challenging time for the Indian auto industry,'' Tata Motors Chairman Cyrus P. Mistry said in the statement.

Net income climbed 71 per cent to 35.4 billion rupees ($566 million) in the three months ended September 30, beating analyst estimates, as sales at the Jaguar Land Rover unit jumped, outweighing a loss at the automaker's domestic division.

Sales at Tata Motors' Indian unit declined 29 per cent in the period.

Slym was the second GM executive to be appointed managing director at Tata Motors.

The company previously hired Carl-Peter Forster in 2010 from GM in Europe.